WASHINGTON — American military forces in Iraq were authorized to pursue former members of Saddam Hussein’s government and terrorists across Iraq’s borders into Iran and Syria, according to a classified 2005 document that has been made public by an independent Web site.

The document, which was disclosed by the organization Wikileaks and which American officials said appeared authentic, outlined the rules of engagement for the American division that was based in Baghdad and central Iraq that year.

It also provided instructions for how to deal with the radical Shiite cleric Moktada al-Sadr: his status as a hostile foe was “suspended,” and he and his key associates were not to be attacked except in self-defense.

Wikileaks, a Web site that encourages posting of leaked materials, says its goal in disclosing secret documents is to reveal “unethical behavior” by governments and corporations. It has previously posted the United States military’s manual for operating its prison in Guantánamo Bay, Cuba; a military assessment of a 2004 attack in Falluja; and lists of American military equipment in Iraq.

The American military command in Baghdad on Sunday sharply criticized the group’s decision to post the document.

“While we will not comment on whether this is, in fact, an official document, we do consider the deliberate release of what Wikileaks believes to be a classified document is irresponsible and, if valid, could put U.S. military personnel at risk,” said Rear Adm. Gregory J. Smith, a spokesman for the command.

Rules of engagement in Iraq, which cover the procedures for using force on a battlefield in which insurgents and terrorists mix with civilians, have long been considered highly classified. The American military’s concern is that adversaries will be able to adjust their tactics if they know the rules that describe the specific circumstances in which force may and may not be used.

The 2005 document covers the procedures used by Multi-National Division Baghdad, the American unit that operated in the Iraqi capital and central Iraq. At a time when sectarian divisions had brought Iraq to a low-level civil war, the document suggests that capturing and killing former members of Mr. Hussein’s government was still a concern.

In a section on crossing international borders, the document said the permission of the American defense secretary was required before American forces could cross into or fly over Iranian or Syrian territory. Such actions, the document suggested, would probably also require the approval of President Bush.

But the document said that there were cases in which such approval was not required: when American forces were in hot pursuit of former members of Mr. Hussein’s government or terrorists.

Approval by the defense secretary “is not required to conduct uninterrupted pursuit and engagement of positively identified former regime military aircraft, terrorist and senior [former] military leadership and senior nonmilitary elements of former Iraqi regime command and control across international borders,” the document said.

It stated that the American commander engaged in the pursuit, however, should consult with top commanders in Baghdad, “time permitting.”

It is not known if the authority to conduct hot pursuits across the Iranian and Syrian borders was ever used or what authority exists today. In October 2005, The New York Times reported that there had been a series of clashes between Army Rangers and Syrian troops along the border with Iraq. According to the 2005 document, American forces were also authorized to respond to a “hostile force” that used Syrian or Iranian territory to attack American troops in Iraq or that posed an “imminent threat” to American operations there. They were instructed to consult with a senior American commander if there was time.

Apparently in a carryover from the intelligence failures of the Iraq invasion in early 2003, the document says the United States Central Command, which oversees operations in the Middle East, gave American commanders in Iraq the authority to attack mobile “W.M.D. labs”; such labs for making germ weapons were later determined not to exist.

The 2005 document also referred to a Central Command list of the “hostile forces” that may be “engaged and destroyed.” It focused heavily on Mr. Hussein’s former security forces, like the Special Republican Guard and members of the Baath Party militia that were said to have shifted from “overt conventional resistance to insurgent methods of resistance.”

Reflecting the clash the year before between American forces and Mr. Sadr’s militia, the document said the militia and other armed supporters of the cleric had also been on the list of paramilitary forces deemed to be “hostile.” L. Paul Bremer III, the head of the American occupation authority in Iraq until June 2004, had branded Mr. Sadr an outlaw, and an Iraqi judge had issued a secret warrant for his arrest.

But a truce was later worked out with Mr. Sadr, and Iraqi politicians sought to bring him into the political process. Apparently as a result of those developments, the rules of engagement were modified. Referring to Mr. Sadr and the Mahdi Army, the document says: “Their status as a declared hostile force, however, is suspended and such individuals will not be engaged except in self-defense.”